Insecticide



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1 Patented Oct. 12,1937 v UNITED STATES PATENT OFFICE Donald L. Vivianand Herbert L. J. Bauer, Washington, D. 0., dedicated to the free use ofthe Public in the territory of the United States of America No Drawing.

' Application June 27, 1936,

Serial No. 87.746

7 Claims.

(Granted under the m oi' 8March s, 1883, as

terials for destroying or checking the growth or' multiplication ofliving organisms, whether plant or animal, which are economicallyinjurious man.

An object of the invention is to provide'materials suitable for useasinsecticides.

Another object of the invention is to provide a material for dusting orspraying delicate vegeplants grown under glass, which will not causeinjury to foliage.

Another object of the invention is to provide a material which isrelatively non-toxic to man and domestic animals when taken by mouth,and which can be used in place of lead arsenate and other arsenicals fordestroying insects without leaving harmful residues on fruits andvegetables. We have found that substances belonging to a certain classof organic compounds have a specific toxic effect upon harmful insects,and our invention consists in the application of said substances to thedestruction of insect pests.

The novel insecticides found by us belong to the class of organiccompounds which contain in their molecules, according to acceptedformulation, two homocyclic nuclei joined by'an azo linkage, that is, bythe -N=N group, and which contain, in addition,one or more substituentschosen from the group comprising halogen atoms, nitro groups, and aryl,alkyl, or aralkyl o ps- Typical representatives of this class ofcompounds are:

- p-ilnomazobenzene PG Q p, '-dichioroszobenzcnc i p-iodosrobenzeneamended April 30, 1928;

tation such as bean plants, peach trees, and v p-bromoazobenzene p,pf-dibromoazobenzene i-iodoz methyl-4-nitroazobenmnc p-nitro-szobenzenep-iodo-p-nitro-azobenzene but these examples are representative only,and are not intended to comprise all the compounds which fall under thedefinition of the paragraph immediately above.

These compounds may be made in various ways,

all well known to those skilled in the art, as, for example, byreduction of nitro compounds under appropriate conditions, byreplacement ofthediazonium group in p-phenylazo-phenyl diazonium saltsby halogen, or in some cases by direct halogenation. Variations in themethods of preparation can readily be made, but these methods do notaffect the novel features claimed.

' For a specific example of the toxicity of these compounds it may bementioned that when piodoazobenzene was dissolved in acetone and theresulting solution poured'into water, there resulted a mortality of morethan 50% of culicine mosquito larvae within 16 hours when theconcentration of azo compound was one part to 10,000 parts of water.

These substituted azo compounds may be applied in amanner similar tothat in which insecticides in general are used, that is, as dusts,

, or in the form of solutions or suspensions in various media, such aswater, kerosene, etc., and either with or without the use of spreaders,wetting agents, or sticking agents.

Having thus described our invention we claim:

1. An insecticide comprising an arylazo compound in which the nuclei aresubstituted by at least one halogen atom.

'2. An insecticide comprising an arylazo compolmd in which the nucleiare substituted by at least one nitro group.

3.1An insecticide comprising an arylazo compound in which the nuclei aresubstituted by at least one halogen atom in addition to at least one 6.1m insecticide comprising an arylazo comnitro group. 7 pound inwhich'the nuclei are substituted by at 4. An insecticide comprisinganarylazo comleast one'halogen atom, in addition to at least pound inwhich the nuclei are substituted by at one nitro group and at least onegroup chosen 5 least one halogen atom in addition to at least one fromthe list consisting of aryl, alkyl, and aralkyl 5 group chosen from thelist consisting oi aryl, groups. I albl, and aralkyl'grohps. Y 7. Aninsecticide containing as'its essential ac- 5. An insecticide comprisingan arylazo comtive ingredient p-iodoazobenrene. pound in which thenuclei are substituted by at 10 least one nitro group, in addition to atleast one DONALD L. VIVIAN.

group chosen from the list consisting 0! an]. HERBERT L. J. HALLER.aikyl, and aralkyl s m-

